US Bridges

SR 432 over Solo Slough

Good

Cowlitz County, Washington · 2.8 E JCT SR 4 · Structure no. 002001110000000

Built
1961
64 years old
Condition
Good
inspected September 2022
Type
Culvert
Steel
Length
23 ft
1 main span
Daily traffic
6,580
2023 count
Owner
State
State Highway Agency

About this bridge

SR 432 over Solo Slough is a steel culvert carrying SR 432 over Solo Slough in Cowlitz County, Washington. It was built in 1961, so it is 64 years old, older than the Washington average of 49.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 6,580 vehicles a day, roughly 10% of them trucks, projected to reach 8,459 by 2039. The structure is 23 ft (7 m) long. If it were closed, the detour would be 1.9 mi (3 km).

Location

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CarriesSR 432
CrossesSolo Slough
Location2.8 E JCT SR 4
RouteState Highway 432
CountyCowlitz County
StateWashington
Coordinates46.14698, -123.0029
Functional classUrban Other Principal Arterial

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection8 Very GoodNo problems noted.
Culvert7 GoodSome minor problems.
Last inspectionSeptember 2022
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating99 US tons
Inventory rating99 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans1
Design loadHS 20
Structure length23 ft (7 m)
Longest span23 ft (7 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,580 (2023)
Projected traffic8,459 by 2039
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$371,000 (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SR 432 over Solo Slough built?

It was built in 1961, making it 64 years old in 2025.

What condition is SR 432 over Solo Slough in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in September 2022.

How much traffic does SR 432 over Solo Slough carry?

About 6,580 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is SR 432 over Solo Slough?

The structure is 23 ft (7 m) long with a longest span of 23 ft (7 m).

Who owns SR 432 over Solo Slough?

It is owned by the State Highway Agency.